HSCSD (High-Speed Circuit Switched Data) - definition

A system for data calls on GSM networks that came before packet based systems such as GPRS and EDGE.

HSCSD is the "high-speed" variant of CSD (maximum speed of 9.6 kbps) that has better error-correction codes that give a boost in speed of about 50% and allows several call channels to be used as one - up to four channels - resulting in a maximum speed of 57.6 kbps.